This invention relates generally to the ink-jet printing art for ejecting ink droplets onto a recording medium such as paper, and more particularly, to an ink tank cartridge for use in an ink-jet type recording apparatus such as a printer.
In a conventional recording apparatus, ink is supplied to a recording head from an ink tank constructed as a cartridge. A benefit of using an ink cartridge serving as an ink tank is that ink does not smear due to the leakage of ink while refilling new ink or the like. Controlling the flow of ink from the cartridge is also a concern.
In a tri-color or a multi-color cartridge used with an ink-jet printer, a separate chamber is provided for each color, for example, cyan, magenta, and yellow ink. Each of the three chambers uses a separate ink color to feed the printhead. In most cases, each color ink has its own unique viscosity, different from the other inks which means that each ink flows at a different rate through the printhead. Accordingly, larger and smaller drop sizes are formed because of the different viscosity of the particular ink.
In a semi-free ink cartridge design that has a porous member compressed within a chamber, the porous members are typically of equal size and are compressed into each chamber the same amount. Because each foam block is compressed in the same proportion, and the ink viscosity is different for the different color inks, ink flow rate to the nozzle is unequal. This non-uniform drop size impacts on print quality.
Accordingly, a new and improved ink cartridge which would overcome these deficiencies and others while meeting the above-stated needs is desired.
Generally speaking, in accordance with the invention, an ink tank cartridge is provided for an ink-jet type recording apparatus removably mounted on the ink supply needle of a recording body.
More particularly, the invention relates to an ink tank cartridge for an ink-jet type recording apparatus having a housing including a plurality of walls forming a cavity. A divider wall divides the cavity into first and second chambers. A pair of removable spacers are inserted into each of the chambers and further divide each chamber into substantially equally sized smaller sub-chambers. Ink absorbing members are inserted into one of the sub-chambers of each chamber where the ink absorbing members are compressed by the spacers to regulate the flow of ink through the ink absorbing members. A second divider wall along with the first divider wall separates the cavity of the housing into first, second, and third chambers. A third spacer is inserted into the third chamber to divide it into substantially equally sized sub-chambers. An ink absorbing member is also installed into one of the sub-chambers of the third chamber.
Each removable spacer has a first leg, a second leg, and a wall hingedly connected between the legs. The legs are spaced apart and substantially parallel to each other. Each wall of the spacer has a notch for permitting ink flow between sub-chambers of a particular chamber. Each of the chambers is filled with an ink of different viscosities. The ink absorbing members are compressed in proportion to the viscosity of the ink carried by the ink absorbing member. The legs of the spacer in the chamber with the ink of highest viscosity have a longer length than legs of a spacer in a chamber of ink with lower viscosity. As a result, the longest length legs provide the greatest amount of compression for their corresponding ink absorbing member which carries ink of highest viscosity. In contrast, the shortest length legs provide the least amount of compression on their corresponding ink absorbing member which carries ink of lower viscosity.
Still other aspects of the invention will become apparent to those skilled in the art upon reading and understanding the following detailed description.